Model-Corrected Microwave Imaging through Periodic Wall Structures by Paul C. Chang, Robert J. Burkholder, John L. Volakis

“…In addition to propagation delays caused by the wall, it is shown that the structural periodicity induces high-order space harmonics leading to other ghost artifacts in the through-wall image. …”
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Dephasingless two-color terahertz generation by Tanner T. Simpson, Jeremy J. Pigeon, Kyle G. Miller, Dillon Ramsey, Dustin H. Froula, John P. Palastro

“…Abstract A laser pulse composed of a fundamental and an appropriately phased second harmonic can drive a time-dependent current of photoionized electrons that generates broadband THz radiation. …”
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Failure Diagnosis for Demagnetization in Interior Permanent Magnet Synchronous Motors by Takeo Ishikawa, Naoto Igarashi, Nobuyuki Kurita

“…The back-EMF is proportional to permanent magnet volume, and there is no difference in the demagnetization in the radial direction and in the axial direction. Even harmonics and subharmonics of flux density at the teeth tip could be useful for diagnosis if a search coil is installed there. …”
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Regressions on quantum neural networks at maximal expressivity by Iván Panadero, Yue Ban, Hilario Espinós, Ricardo Puebla, Jorge Casanova, Erik Torrontegui

“…We attribute this enhancement to a larger survival set of Fourier harmonics when decomposing the output signal.…”
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Experimental Study on the Vibration of an Overhung Rotor with a Propagating Transverse Crack by S.A. Adewusi, B.O. Al-Bedoor

“…The steady state results showed that the propagating crack produces changes in vibration amplitudes of 1X and 2X vibration harmonics and excites 3X harmonic just before fracture. …”
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Improved Power Control Using Optimal Adjustable Coefficients for Three-Phase Photovoltaic Inverter under Unbalanced Grid Voltage by Qianggang Wang, Niancheng Zhou, Xiaoxuan Lou, Xu Chen

“…Three coefficients are brought in to tune the output current reference within the required limits of the power quality (the current harmonic distortion, the AC current peak, the power fluctuation, and the DC voltage fluctuation). …”
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Design and analysis of electromagnetic and mechanical structure of ultra-high-speed slotted solid rotor induction motor by Jiawei Yi, Zhihao Zhu

“…Then, by constructing a two-dimensional finite element model, the slot matching scheme and coil pitch are optimized, and the influence of different slot matching scheme and coil pitch on the output torque and harmonics of the motor is compared. Then, the influence of rotor slot size on electromagnetic and mechanical properties of the motor is described in detail. …”
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Enhancing power quality in high-power renewable applications using a new extendable nine-level grid-tied converter by Shivam Kumar Yadav, Bhim Singh

“…Converter employs polynomial-based selective harmonics elimination (SHE) to switch at fundamental frequency, ensuring efficiency in steady-state and dynamic conditions. …”
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Compensation of active filter using p-q theory in photovoltaic systems by Farzane Soleimani Rudi, Mohammad Naser Hashemnia

“…This work proposes an active shunt filter design for grid-connected solar systems, utilizing the p-q instantaneous power theory technique to minimize grid harmonics and reduce reactive power. As a result, the total harmonic distortion (THD) is decreased, and the power quality of the network is improved. …”
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The earth-fill dam state express investigation using mechanical vibrations produced by HPP by Galina Antonovskaya, Natalia Kapustian

“…Such vibrations are monochromatic oscillations at main frequencies and their harmonics produced by turbine. Seismic sensors installed on the dam's crest and inside it, if it possible, and in the area of abutment contacts register microseisms include HPP turbine operation vibrations which may be extracted by seismic data processing, i.e., filtering. …”
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DAMAGE DETECTION OF COMPOSITE PLATE BASED ON LOCAL DEFECT RESONANCE INTER-MODULATION EFFECT by CHEN WenJian, QU WenZhong, XIAO Li

“…Comparing with nonlinear ultrasonic nondestructive testing method using harmonic signals and modulation methods, the local defect resonance（LDR） inter-modulation effect can greatly enhance the nonlinear behavior between the damaged interfaces,also,it uses the modulation between input signal and LDR frequency thus the input signal is simplified. …”
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Performance Analysis of Grid-Connected Distributed Generation System Integrating a Hybrid Wind-PV Farm Using UPQC by Tongfei Lei, Saleem Riaz, Noor Zanib, Munira Batool, Feng Pan, Shaoguo Zhang

“…Along with providing active power (AP) to the utility grid, Wind-PV-UPQC improves PQ indicators, for example, voltage drops/surges, harmonics of grid voltages, and PF. Since Wind-PV-UPQC depends on dual compensation scheme, the parallel converter works as a sinusoidal voltage source, while the series converter works as a sinusoidal current source. …”
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Orbital and suborbital temperature variability in the central Mediterranean across the Pliocene/Pleistocene transition. by Elena Zanola, Teresa Rodrigues, Sergio Bonomo, Patrizia Ferretti, Eliana Fornaciari, Agata Di Stefano, Alessandro Incarbona, Nereo Preto, Isabella Raffi, Luca Capraro

“…Alternatively, it may be interpreted as the resonance (i.e., harmonics) of the low-latitude precessional forcing in mid-latitude regions. …”
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Different‎ Magnetic Field ‎Distributions‎ in Deformed Neutron Stars‎ by Mina Zamani, Mohsen Bigdeli

“…The second formalism for investigating macroscopic properties of magnetars is gained by treating the nonuniform pressure as a perturbation to the total pressure and expanding metric and pressure up to the quadrupole term in spherical ‎harmonics.‎Afterwards‎, ‎we include three nucleon interactions (TNI) to ‎the ‎EoS‎ and apply this model to represent our results for both exponential and polynomial magnetic field profiles.‎The maximum gravitational mass is obtained ‎in ‎the ‎range ‎of ‎(‎1.7‎1-1.80)‎ M. ‎and ‎(‎2.13‎‎-‎2.1‎9)‎‎‎ M.‎ for ‎the EoS without and with TNI ‎contribution‎, respectively.…”
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Dynamic Response Analysis of the Cracked Fault Gear System Based on the Finite Element Model by Jiao Wei, Xu Kejun, Qin Haiqin

“…The results show that when there is a crack in the tooth root, the acceleration response has a periodic impact characteristic, and the side frequency phenomenon in the frequency domain occurs near the meshing frequency and its harmonics; the strength of impact components in both the time and frequency domains is positively correlated with crack depth and rotational speed. …”
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Effect of Impeller Inlet Geometry on Cavitation Performance of Centrifugal Pumps Based on Radial Basis Function by Shuwei Zhang, Renhui Zhang, Sidai Zhang, Junhu Yang

“…The lower the pressure pulsation for blade passing frequency and the second harmonics of the samples is, the better the cavitation performance is. …”
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Numerical Studies of Propeller Exciting Bearing Forces under Nonuniform Ship’s Nominal Wake and the Influence of Cross Flows by Huilan Yao, Huaixin Zhang

“…Numerical results were widely validated by measured data, especially the velocity field at the propeller plane. Harmonic characteristics of the nonuniform ship’s wake were studied. …”
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Dynamic Characteristic Analysis of the Main Drive Gear Transmission System of a Large Shield Machine Considering Non-uniform Load Conditions by Deng Shuzhi, Xu Lixin, Long Bin, Su Cuixia

“…The maximum amplitude of the dynamic meshing force of the gear and the contact force of the bearing raceway occur at the corresponding meshing frequency and its harmonics, exhibiting obvious low-frequency vibration characteristics.Under non-uniform load conditions, there is a significant uneven load phenomenon in the meshing force between the small gears and the inner ring gear of the main drive group.…”
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Gear Defect Modeling of a Multiple-Stage Gear Train by Andrew Sommer, Jim Meagher, Xi Wu

“…Frequency analysis shows the appearance of side band modulations as well as harmonics of the gear mesh frequency. A joint time-frequency response analysis during startup illustrates the manner in which contact forces increase during acceleration.…”
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Compact Quadband Bandstop Filter Based on Concentric Split Ring Resonators with Perturbation for Multifunctional Wireless Systems by Pierre Moukala Mpele

“…Bandstop filters play an essential role in many radio frequency (RF) and microwave communication systems to block undesired signals or reject spurious harmonics. This paper presents the design and experiment of a compact quadband bandstop filter centered at 1.2/1.97/2.96/4.78 GHz with a passband insertion loss ranging from 1.07 to 2.9 dB. …”
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